To Know How To Use Blockquote First We Want to Know,What Is Blockquote ?
Blockquote :
The <blockquote> tag specifies a section that is quoted from another source.
Browsers usually indent <blockquote> elements
To Add This To Blogger Posts
Just Select The Text and Click On The blockquote Which Is Located At Tab as shown Below
Now Your Done...
To Customize BlockQuote Read This Post